JP2006066273A - Image display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image display device that suffers little degradation in electron source characteristics with time and suffers hardly noticeable unevenness of brightness or color shift of the image. <P>SOLUTION: The image display device comprises: an electron source substrate 101 on which a plurality of electron emitting elements 104 are arranged; an image-forming substrate 112 opposed to the substrate 101 and having a phosphor film 111 and an anode electrode film 110; and a magnetic field generating means 121. A component of a flux density of the magnetic field generated by the magnetic field generating means 121 parallel to the electron source substrate 101 is 0.01 tesla or lower at the position of the electron emitting elements 104. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image display device using an electron-emitting device.

  A large number of electron-emitting devices are arranged on a flat substrate as an electron source, and an electron beam emitted from the electron source is irradiated to a phosphor as an image forming member on the opposite substrate, and the phosphor is caused to emit light to display an image. In the flat display, it is necessary to keep the inside of the vacuum vessel containing the electron source and the image forming member in a high vacuum. When gas is generated inside the vacuum vessel and the pressure rises, the degree of the effect varies depending on the type of gas, but it adversely affects the electron source and reduces the amount of emitted electrons, making it impossible to display a bright image.

  Especially in flat displays, the gas generated from the image display member accumulates in the vicinity of the electron source before reaching the getter installed outside the image display area, and is characterized by local pressure rise and accompanying electron source deterioration. Problem. Japanese Patent Application Laid-Open No. 9-82245 (Patent Document 1) describes that a getter is arranged in an image display area, and the generated gas is immediately adsorbed to suppress deterioration and destruction of the element. Japanese Patent Application Laid-Open No. 2000-133136 (Patent Document 2) shows a configuration in which a non-evaporable getter is disposed in an image display area and an evaporative getter is disposed outside the image display area. Furthermore, as shown in Japanese Patent Laid-Open No. 2000-315458 (Patent Document 3), it has been devised to perform degassing, getter formation, and sealing (vacuum containerization) in a vacuum chamber in a series of operations.

  There are two types of getters: evaporative getters and non-evaporable getters, but evaporative getters have a very high exhaust rate for water and oxygen. Both types of getters have almost no exhaust speed. The argon gas is ionized by the electron beam to become positive ions, which are accelerated by the electric field for accelerating the electrons and collide with the electron source, thereby damaging the electron source. Further, in some cases, an electric discharge may be generated inside, and the device may be destroyed.

As an exhausting means capable of exhausting a rare gas, Japanese Patent Application Laid-Open No. 5-121012 (Patent Document 4) describes a method of maintaining a high vacuum for a long time by connecting a sputter ion pump to a vacuum vessel of a flat display. . As shown in FIG. 9, the thin flat display device includes a front panel 902 having a phosphor screen 901 and a container main body 903 that is hermetically sealed with the front panel 902 and constitutes a vacuum container 910 by cooperating with the front panel 902. The electrode assembly 905 is disposed in the container main body 903. The electrode assembly 905 has a field emission cathode, and an electron beam emitted from the cathode is modulated by an internal electrode 915, that is, a modulation electrode, and is directed toward the phosphor screen 901 to display an image. An ion pump 908 is connected to the container body 903 to maintain a vacuum, and the inside of the vacuum container 910 is maintained at a pressure of 10 ⁻⁶ Pa (10 ⁻⁸ torr) or less. As an embodiment of the ion pump 908, for example, 1000 gauss (0.1 Tesla, hereinafter, unit tesla of magnetic flux density is expressed as T) is applied by the magnetic field generating means 920, and 3 to 5 kV is applied between the anode 912 and the cathode 913. By applying a high voltage and operating the ion pump 908, a pressure of 10 ⁻⁶ Pa or less, for example, an ultrahigh vacuum of about 10 ⁻⁸ Pa can be obtained.

However, the magnetic field leaked from the magnetic field generating means 920 acts on the electron beam for displaying an image, changes the trajectory of the beam, and causes a deviation from the position that should be originally reached when reaching the phosphor. For this reason, there is a problem in that it collides with a member other than the phosphor, reaches the adjacent phosphor, and the luminance is lowered, or color shift occurs in a color image.
JP-A-9-82245 JP 2000-133136 A JP 2000-315458 A Japanese Patent Laid-Open No. 5-121012

  The present invention has been made in view of such problems, and an object of the present invention is to provide an image display device in which unevenness in luminance and color misregistration of an image are reduced.

  The present invention relates to the following matters.

1. An image display device comprising: an electron source substrate on which a plurality of electron-emitting devices are arranged; an image forming substrate disposed opposite to the electron source substrate and having a fluorescent film and an anode electrode film; and a magnetic field generating means. ,
An image display device, wherein a component parallel to the electron source substrate of the magnetic flux density of the magnetic field generated by the magnetic field generating means is 0.01 Tesla or less at the position of the electron-emitting device.

  2. 2. The image display device according to claim 1, wherein the magnetic field generating means is a permanent magnet of an ion pump connected to the electron source substrate or the image forming substrate.

  3. 3. The image display device according to 2 above, wherein the magnetic field generating means is a single permanent magnet having a pair of magnetic poles.

  4). 4. The image display device according to 3 above, wherein the direction of the magnetic pole is substantially perpendicular to the electron source substrate.

  5. 2. The image display device as described in 1 above, wherein a distance between the magnetic field generating means and the electron emitting element closest to the magnetic field generating means is 5 mm or more.

  6). 2. The image display device according to 1 above, wherein the magnetic field generating means is a permanent magnet attached to a speaker.

  According to the present invention, the component parallel to the electron source substrate of the magnetic flux density of the magnetic field generated from the magnetic field generating means is not more than a predetermined intensity at the position of the electron-emitting device. It is possible to provide an image display device in which the deflection of the electron beam due to the magnetic field is small and the luminance unevenness and color shift of the image are hardly noticeable.

  In an embodiment using a single permanent magnet having a pair of magnetic poles, for example, an ion pump is directly connected to the electron source substrate or the image forming substrate, and the permanent magnet is installed at a position close to the electron-emitting device. Even when it is necessary to do so, the magnetic flux density rapidly decreases when the magnet is separated from the permanent magnet, so that the influence on the electron beam can be reduced.

  In the present invention, since the amount of electrons other than the phosphor is reduced, the amount of emitted gas is small, so that the lifetime of the electron source is extended and the lifetime of the getter is extended.

  Hereinafter, preferred embodiments will be described in detail with reference to the drawings. In the following description, the electron source substrate will be described as a rear plate, and the image forming substrate will be described as a face plate.

  FIG. 1 is an example of a schematic diagram showing a configuration of an image display apparatus of the present invention. As shown in FIG. 1, the rear plate 101 has an upper wiring 102 and a lower wiring 103 formed inside a substrate such as glass, and a plurality of surface conduction electron-emitting devices 104 as electron sources. In 112, a phosphor film 111, a metal back film 110 as an anode electrode film, and a getter film 109 are formed inside a transparent glass substrate. The support frame 105 is joined by the rear plate 101 and the joining member 106, and the face plate 112 is joined by the joining member 107 to form an envelope that is a vacuum container. The plurality of spacers 108 are atmospheric pressure support members.

  The ion pump 123 is joined to the exhaust port 113 of the rear plate 101 by a part of the ion pump container 115 and a joining member 114 such as frit glass. The ion pump container 115 includes a cylindrical anode electrode 119 and an opposing cathode electrode 116, and has an anode connection terminal 120 and a cathode connection terminal 118. A metal plate 117 is installed on the cathode electrode 116. Further, a permanent magnet 121 attached to a yoke 122 as a magnetic field generating means is installed outside the ion pump container 115. The anode connection terminal 120 and the cathode connection terminal 118 are vacuum-tight terminals for supplying a high voltage to the anode electrode 119 and the cathode electrode 116.

  FIG. 2A is a schematic view showing a part of the surface conduction electron-emitting device 104 installed on the rear plate 101 and wiring for driving the electron source. In the figure, a lower wiring 103, an upper wiring 102, an interlayer insulating film 201 for electrically insulating the upper wiring 102 and the lower wiring 103, and the like are shown.

  FIG. 2B shows the structure of the surface conduction electron-emitting device 104 of FIG. 2A in an enlarged view from A to A ′, and shows device electrodes 202 and 203, a conductive thin film 205, and an electron-emitting portion 204. Etc. are shown.

In the configuration of FIG. 1, as the rear plate 101 and the face plate 112, a general glass substrate or a glass substrate on which various functional films such as SiO ₂ are formed is used.

  As a material for the device electrode (corresponding to 202 and 203 in FIG. 2) of the surface conduction electron-emitting device 104, a general conductor is used. As a manufacturing method, use a vacuum deposition method, a sputtering method, a chemical vapor deposition method, or the like to form an electrode material, and process it into a desired shape by photolithography technology (including processing technologies such as etching and lift-off). It can also be produced by other printing methods. In short, it is only necessary that the desired element electrode material can be formed into a desired shape, and the manufacturing method is not particularly limited.

  In order to obtain good electron emission characteristics, the conductive thin film 205 is preferably a fine particle film composed of fine particles. The conductive thin film 205 is formed, for example, by applying an organic metal thin film using an ink jet coating apparatus or the like, followed by heat baking treatment. Other methods for forming the conductive thin film 205 include a vacuum deposition method, a sputtering method, a chemical vapor deposition method, a dispersion coating method, a dipping method, a spinner method, or a method combined with processing techniques such as lift-off and etching. May be.

  The electron emission portion 204 is a high-resistance crack formed in a part of the conductive thin film 205, is formed by a process called energization forming, and it is desirable to further perform a process called activation on the element. Next, an arrangement of a plurality of surface conduction electron-emitting devices 104 and wirings for supplying electric (power) signals for image display to the devices will be described.

  As an example of wiring, two orthogonal wirings (Y: upper wiring 102 and X: lower wiring 103, which are called simple matrix wirings) can be used. An upper wiring 102 and a lower wiring 103 are connected to the device electrodes 202 and 203 of the surface-type electron-emitting device 104, respectively. The upper wiring 102 and the lower wiring 103 can be made of a conductive metal or the like formed by using a printing method such as a vacuum deposition method, a screen printing method, an offset printing method, a sputtering method, and the like. The width is designed as appropriate. Among them, it is preferable to use a printing method that is inexpensive to manufacture and easy to handle. Further, where the upper wiring 102 and the lower wiring 103 overlap, an interlayer insulating film 201 is sandwiched between them to obtain electrical insulation. The interlayer insulating film 201 can be formed by a production method similar to the production method of the upper wiring 102 and the lower wiring 103.

  The phosphor film 111 applied to the inside of the face plate 112 is composed of only a single phosphor in the case of monochrome. However, when displaying a color image, the phosphor emitting three primary colors of red, green, and blue is black conductive. The structure is separated by materials. The black conductive material is called a black stripe or a black matrix depending on its shape. As a manufacturing method, there are a photolithography method using a phosphor slurry or a printing method. Patterning is performed on pixels of a desired size to form phosphors of respective colors.

  A metal back film 110 that is an anode electrode film is formed on the phosphor film 111. The metal back film 110 is made of a conductive thin film such as Al. The metal back film 110 improves the luminance by reflecting light traveling in the direction of the rear plate 101 among the light generated in the phosphor film 111. Further, the metal back film 110 imparts conductivity to the image display area of the face plate 112 to prevent electric charges from accumulating, and serves as an anode electrode for the surface conduction electron-emitting device 104 of the rear plate 101. It is. In order to apply a high voltage to the metal back film 110, it is electrically connected to a high voltage application device.

  The joining member 107 that joins the support frame 105 and the face plate 112 and the joining member 106 that joins the support frame 105 and the rear plate 101 are preferably a low-melting-point metal or alloy such as indium that can be vacuum-tight, or frit glass. In other words, the means is not limited as long as the vacuum tightness is maintained.

  Also, the ion pump container 115 and the rear plate 101 are preferably joined by a low-melting-point metal or alloy such as indium that can be vacuum-tight, or frit glass. Similarly, the means is not limited as long as the vacuum tightness is maintained.

  As the material of the getter film 109, metals such as Ba, Mg, Ca, Ti, Zr, Hf, V, Nb, Ta, and W, and alloys thereof can be used.

  The spacer 108 is a member for supporting the image display device so as not to be destroyed by the atmospheric pressure, and has an appropriate mechanical strength, sufficient electric withstand voltage, and electric characteristics that do not adversely affect the electron beam. Yes.

  On the surface of the cathode electrode 116 of the ion pump 123, a metal plate 117 of Ti, Ta or the like is installed to increase the adsorption performance. A metal or an alloy can be used as the material of the cathode electrode 116 and the anode electrode 119, but a stainless alloy is preferable because of its emission gas characteristics and oxidation resistance. The material of the ion pump container 115 can be glass, metal, ceramics, etc., and is not particularly limited as long as it can be maintained in a vacuum and can pass a magnetic field.

  The magnet 121 is preferably a permanent magnet made of a material such as ferrite, samarium-cobalt alloy, neodymium alloy, or alnico alloy. The magnet 121 is preferably attached to the yoke 122 as shown in the figure, so that leakage magnetic flux can be reduced. In a space surrounded by the cathode electrode 116 and the anode electrode 119, it is preferable to generate a magnetic field having a magnetic flux density of 0.08 T or more.

  When a part of the magnetic field generated from the magnet reaches the electron beam, the trajectory of the electron beam is changed. Since the main part of the electron beam travels vertically from the rear plate 101 toward the face plate 112, the component perpendicular to the rear plate 101 of the magnetic field has little influence on the trajectory of the electron beam. Therefore, when the deflection of the electron beam trajectory is a problem, the magnetic flux density component parallel to the rear plate may be considered. Therefore, when the influence of the magnetic field on the image was examined, when the magnetic flux density component parallel to the rear plate was 0.01 T at the position of the electron-emitting device, the influence on the image was not problematic for 48 out of 50 persons. It was judged.

  In the present invention, the component parallel to the rear plate of the magnetic flux density of the magnetic field generated from the magnet is configured to be 0.01 T or less at the position of the electron-emitting device.

  In the conventional ion pump, two permanent magnets are paired, and the axis of the cylindrical anode electrode 119 is parallel to the direction of the magnetic flux density and is installed around the ion pump container 115 so as to attract each other. Thereby, a uniform magnetic flux density is obtained in a wide range in the space surrounded by the cathode electrode 116 and the anode electrode 119, and the chance of ionization is increased, so that the exhaust speed is improved. On the other hand, in one embodiment of the present invention, one permanent magnet having a pair of magnetic poles is used. When a single permanent magnet is used, the uniform magnetic flux density region is narrowed and the exhaust speed is reduced. However, the magnetic flux density is rapidly reduced when the magnet 121 is separated from the magnet 121. Therefore, the influence on the electron beam for image display is reduced. Is further reduced. The material of the yoke 122 is preferably an alloy such as iron, nickel or permalloy. In particular, as shown in FIG. 1, it is preferable that the direction of the magnetic pole of the permanent magnet of the ion pump (direction of SN) be as vertical as possible to the rear plate so that the magnetic flux density in the parallel direction of the rear plate is reduced. For example, it is in the range of 90 ° ± 45 °, preferably in the range of 90 ° ± 30 °, more preferably in the range of 90 ° ± 15 °, and most preferably substantially vertical (range of 90 ° ± 5 °).

  With such a configuration, in a space surrounded by the cathode electrode 116 and the anode electrode 119, a magnetic field having a magnetic flux density of 0.08 T or more is generated, and a component parallel to the rear plate of the magnetic flux density is The position can be easily set to 0.01 T or less. At this time, the distance from the yoke to the nearest electron-emitting device can be selected in the range of 5 mm or more, preferably 10 mm or more.

  A voltage of 1 kV to 10 kV is applied to the anode electrode 119 and the cathode electrode 116 through the anode connection terminal 120 and the cathode connection terminal 118 so that the anode electrode becomes positive. As the applied voltage increases, the power consumption increases, and the harmful effect that insulation measures must be taken reliably increases. Therefore, 2 to 5 KV is suitably used as the voltage for driving the ion pump 123 efficiently. When the voltage is applied, discharge occurs using the electrons remaining in the space surrounded by the anode electrode 119 and the cathode electrode 116 as seeds. The cations of the residual gas generated by the discharge collide with the metal plate 117 on the cathode electrode 116 and sputter a substance (for example, Ti) constituting the metal plate 117. The sputtered metal is active and chemically adsorbs the residual gas and acts as a vacuum pump. In addition, ions are implanted into the cathode electrode 116 or the metal plate at the time of collision, become neutral particles by changing their direction and are also implanted into the anode electrode 119, and are covered with a sputtered substance so that they cannot be easily escaped. Noble gases can also be exhausted.

  In the above-described configuration, the voltage is applied to the ion pump 123, and surface conduction electron emission is performed from a scan driving circuit (not shown) connected to the upper wiring 102 and a modulation driving circuit (not shown) connected to the lower wiring 103. A scanning signal and a modulation signal which are image signals are applied to the element 104. As a result, an electron beam according to the electric signal is generated from the surface conduction electron-emitting device 104 and is accelerated by a high voltage (1 to 15 KV) applied to the metal back film 110 and the phosphor film 111, and the phosphor film 111. And the phosphor emits light and displays an image.

When the image is displayed, gas is released from the part where the electrons collide. Gases such as H ₂ , O ₂ , CO, CO ₂ , and H ₂ O that affect the characteristics of the inner surface conduction electron-emitting device 104 of these gases are adsorbed by the getter film 109. On the other hand, Ar, which is an inert gas, is not adsorbed by the getter film 109 but is exhausted by the ion pump 123 attached to the rear plate 101, and the Ar partial pressure is reduced to 10 ⁻⁶ Pa or less, which is a pressure that affects the device. It is possible to suppress the deterioration of the surface conduction electron-emitting device 104 due to Ar. Therefore, an image display apparatus having a long life with little deterioration in luminance even when an image is displayed for a long time can be obtained.

  The electron source as an electron emitting means may be a flat type in which the surface conduction electron-emitting device 104 is formed in a planar shape on the surface of the rear plate 101, or a vertical type formed on a surface perpendicular to the rear plate 101. Furthermore, there is no particular limitation as long as it is an element that emits electrons, such as a thermionic source using a hot cathode, a field emission type electron emitting element, or the like. The power supply method to the electron source is not limited to the simple matrix type, and the present invention can also be applied to an image display device that displays an image by controlling an electron beam emitted from the electron source using a control electrode (grid electrode wiring).

  The ion pump 123 may be installed on the face plate 112 in addition to the rear plate 101, and in this case, the application of the present invention is possible.

  Further, not only the influence from the magnet of the ion pump but also the influence of the leakage of the magnetic field from the permanent magnet attached to the speaker, similarly, the component parallel to the rear plate of the magnetic flux density of the magnetic field is 0 at the position of the electron-emitting device. By setting the value to 0.01 T or less, it is possible to provide an image display device in which the luminance unevenness and the color shift of the image are extremely reduced.

  Hereinafter, examples of the present invention will be described with reference to the drawings. However, the present invention is not limited to these, and can be appropriately changed without departing from the gist of the present invention.

<Example 1>
In this embodiment, the image display apparatus shown in FIG. 1 will be described.

First, a method for manufacturing an envelope which is a vacuum container of an image display device will be described. A glass plate (PD-200: manufactured by Asahi Glass) having a thickness of 2.8 mm and a size of 240 mm × 320 mm as the rear plate 101 and a thickness of 2.8 mm and a size of 190 mm × 270 mm as the face plate 112 is used. A 500 nm SiO ₂ film (not shown) is formed on the electron source side surface, a 50 nm ITO film (not shown) is formed on the back surface, and an 8 mmφ film is formed outside the image area and inside the glass frame 105. What opened the exhaust port 113 was used.

  The device electrodes 202 and 203 of the surface conduction electron-emitting device 104 which is an electron source are formed by depositing platinum on the rear plate 101 by vapor deposition, and by photolithography (including processing techniques such as etching and lift-off). The film was processed into a shape having a film thickness of 100 nm, an electrode interval L = 2 μm, and an element electrode length W = 300 μm.

  Next, the width of the upper wiring 102 (100 lines) is 500 μm and the thickness is 12 μm, the width of the lower wiring 103 (400 lines) is 300 μm and the thickness is 8 μm on the rear plate 101, and printing and baking Ag paste ink, respectively. Formed. A lead-out terminal to an external drive circuit was created in the same manner. The interlayer insulating layer 201 was printed and baked (baking temperature 550 ° C.) with a glass paste, and the thickness was 20 μm.

  Next, the rear plate 101 was washed, sprayed with an ethyl alcohol diluted solution of DDS (dimethyldiethoxysilane; manufactured by Shin-Etsu Chemical Co., Ltd.) by a spray method, and heated and dried at 104 ° C. 0.15 Wt% of palladium-proline complex is dissolved in an aqueous solution of 85% water and 15% isopropyl alcohol as the conductive thin film 205, and an organic palladium-containing liquid is applied by an inkjet coating apparatus, and then at 350 ° C. for 10 minutes. A heat treatment was performed to form a fine particle film made of PdO (palladium oxide), and a conductive thin film 104 having a diameter of 40 μm was obtained.

  The support frame 105 was made of glass (PD-200; Asahi Glass) having a thickness of 2 mm, an outer shape of 150 mm × 230 mm, and a width of 10 mm. LS7305 (manufactured by Nippon Electric Glass Co., Ltd.), which is a frit glass, was applied to the surface connected to the rear plate 101 by a dispenser. Firing was performed by heating at 430 ° C. for 30 minutes.

  The rear plate 101 produced as described above was subjected to the following forming and activation using the vacuum exhaust apparatus shown in FIG. First, as shown in FIG. 3, the rear plate 101 placed on the substrate stage 303 was taken out and the region excluding electrodes (not shown) was sealed with an O-ring 302 and covered with a vacuum vessel 301. The substrate stage 303 has an electrostatic chuck 304 for fixing the rear plate 101 on the stage. Between the ITO film (not shown) formed on the rear surface of the rear plate 101 and the electrodes inside the electrostatic chuck. 1 KV was applied to the rear plate 101 to chuck it.

Next, the steps after the forming step were performed as follows. The inside of the vacuum vessel 301 is evacuated by a magnetic levitation turbomolecular pump 305, evacuated to 10 ⁻⁴ Pa, and a rectangular waveform having a pulse width of 1 msec generated by a signal generator 306 is sequentially connected to a scroll frequency of 10 Hz. The voltage was set to 12V. The lower wiring 103 was grounded. A mixed gas of hydrogen and nitrogen (2% H ₂ , 98% N ₂ ) was introduced into the vacuum vessel, and the pressure was maintained at 1000 Pa. The gas introduction was controlled by a mass flow controller 308, while the exhaust flow rate from the vacuum vessel 301 was controlled by a conductance valve 307 for controlling the flow rate. When the value of the current flowing through the conductive thin film 205 became almost zero, voltage application was stopped. The mixed gas of H ₂ and N ₂ inside the vacuum vessel was exhausted to complete forming, and cracks were formed in all the conductive thin films 205 of the rear plate 101 to create the electron emission portions 204.

Next, an activation process was performed. After evacuating the inside of the vacuum vessel 301 to 10 ⁻⁵ Pa, tolunitrile (molecular weight: 117) was introduced into the vacuum vessel 301 at a partial pressure up to 1 × 10 ⁻⁴ Pa. A rectangular wave pulse having a pulse width of 1 msec generated by the signal generator 306 was applied to the upper wiring 102 to activate all the surface conduction electron-emitting devices 104. After the activation was completed, the tolunitrile remaining in the vacuum vessel 301 was exhausted, and then returned to atmospheric pressure, and the rear plate 101 was taken out.

  The size of the ion pump container 115 is made of glass (PD-200; manufactured by Asahi Glass Co., Ltd.) molded with W30 mm × D30 mm × H30 mm. The ion pump container 115 includes a flat cathode electrode 116 facing the cylindrical anode electrode 119 made of SUS304 stainless steel, and a Ti metal plate 117 is installed at the center of the cathode electrode 116. The cathode electrode 116 and the anode electrode 119 are connected to the cathode connection terminal 118 and the anode connection terminal 120, respectively. The cathode connection terminal 118 and the anode connection terminal 120 are composed of dumet wires, and are fixed in a vacuum-tight state with an ion pump container 115 and a frit so that they can be taken out.

Next, a paste prepared by pasting VS-2 (manufactured by Nippon Electric Glass Co., Ltd.), which is frit glass, with an organic binder was applied to a place (four sides) of the ion pump container 115 to be joined to the rear plate 101 with a dispenser. Further, the entire ion pump container 115 was heated at 400 ° C. for 30 minutes to perform the pre-baking, and further heated and degassed in vacuum at 480 ° C. for 3 hours. The ion pump vessel 115 and the rear plate 101 are temporarily fixed at a desired position in a vacuum baking furnace at a pressure of 10 ⁻⁴ Pa, and heated to 390 ° C. for 80 minutes while being pressurized at a pressure of 5000 Pa. It joined with the joining member 114 which becomes.

  Next, In was applied on the support frame 105, and spacers 108 were installed on the upper wiring 102 every 20 lines. The spacer 108 was provided with an insulating base outside the image display area, and was bonded and fixed with Aron Ceramic W (manufactured by Toagosei Co., Ltd.).

  On the other hand, on the face plate 112, stripe-like phosphors (R, G, B) and black conductive materials (black stripes) are alternately formed as the phosphor film 111, and further a metal back made of an aluminum thin film having a thickness of 200 nm. A film 110 was formed. Next, a bonding member 107 made of In was applied on a silver paste pattern (not shown) provided in advance on the peripheral edge of the face plate 112.

The rear plate 101 and the face plate 112 to which the support frame 105 and the ion pump container 120 are joined are set on the transfer jig 404 of the vacuum processing apparatus shown in FIG. 4, the transfer port 401 is opened, and the load chamber 402 is loaded. After closing the loading / unloading port 401, the load chamber 402 is evacuated to about 3 × 10 ⁻⁵ Pa by the vacuum pump 406. The gate valve 405 was opened, the transfer jig 404 was carried into the vacuum processing chamber 403 that had been evacuated to about 1 × 10 ⁻⁵ Pa by the vacuum pump 407 in advance, and the gate valve 405 was closed. After the transfer jig 404 is in a predetermined position, the rear plate 101 and the face plate 112 are brought into close contact with the upper hot plate 504 and the lower hot plate 505 as shown in FIG. Heated for hours.

  Next, the rear plate 101 and a part of the conveyance jig 404 that supports the rear plate 101 were raised upward by about 30 cm together with the upper hot plate 504. Next, one lid-like jig 503 was moved onto the face plate 112 by rotating the support member 501 in the space between the rear plate 101 and the face plate 112. A current of 12 A was sequentially applied to the Ba getter container installed on the inner ceiling of the lid-like jig 503 every 10 seconds, and the Ba film was deposited on the metal back film 110 of the face plate 112 by 50 nm. The lid-shaped jig 503 was returned to its original position, and the same operation was performed on the other lid-shaped jig 503. Next, the lid-shaped jig 503 is returned to its original position, the support plate and the upper hot plate 504 are lowered, and the upper hot plate 504 and the lower hot plate 505 are heated to 180 ° C. did. After holding at 180 ° C. for 3 hours, the rear plate 101, the support tool that is a part of the transport jig 404 and the upper hot plate 504 are further lowered, and the rear plate 101, the face plate 112, and the support frame 105 are moved to 3.9 MPa. Pressurized with pressure. In this state, the heating was stopped, the mixture was naturally cooled, the temperature was lowered to room temperature, and sealing was completed. Open the gate valve 405, carry the vacuum container from the vacuum processing chamber 403 to the load chamber 402, close the gate valve 405, return the pressure to the load chamber 402 to atmospheric pressure, and then remove the sealed container from the carry-in / out port 401 did. In the sealed container thus produced, no cracks or cracks occurred.

  Next, a neodymium magnet 121 (φ20 mm, thickness 20 mm) was fixed to the soft iron yoke 122, and further fixed to the periphery of the ion pump container 115. At that time, the magnetic flux density in the central portion between the cathode electrodes 116 was set to 0.12T. At this time, the component parallel to the rear plate 101 of the magnetic flux density at the location of the surface conduction electron-emitting device 104 closest to the magnet 121 was 0.01T.

  Next, a DC voltage of 10 kV is applied to the metal back film 110 from a high-voltage power supply (not shown), and a voltage of 3 kV is applied so that the anode electrode 119 becomes positive at the anode connection terminal 120 and the cathode connection terminal 118 of the ion pump 123. The scanning drive circuit (not shown) connected to the upper wiring 102 and the modulation driving circuit (not shown) connected to the lower wiring 103 to the surface conduction electron-emitting device 104 and the scanning signal as an image signal and modulation. A signal was applied to display an image. Even in the image region closest to the ion pump 123, 48 of the 50 judges judged that there was no problem in image non-uniformity and color shift.

  As described above, the image display device created in the embodiment of the present invention has improved image non-uniformity and color misregistration, and has a long life because the ion pump exhausts Ar, and the ion pump has a rear plate. It is contained in a glass housing bonded to the back surface with a frit, and is characterized by no leakage, small size, light weight, high reliability, and low cost.

<Example 2>
In this embodiment, an example in which an ion pump 123 is installed on a face plate 612 will be described as shown in FIG. As shown in the figure, the exhaust port 613 is opened in the face plate 112. In addition, members having the same reference numerals as those shown in the drawings so far indicate the same members. First, a method for manufacturing an envelope which is a vacuum container of an image display device will be described.

  The rear plate 601 is the same as that of the first embodiment except that no exhaust port is provided. Next, as in the first embodiment, the surface conduction electron-emitting device 104, the upper wiring 102, and the lower wiring 103 are formed on the rear plate 601, and the support frame 105 that is the same as that in the first embodiment is sealed. Forming and activation were performed in the same manner as in Example 1. Next, In was applied on the support frame 105, and a spacer 108 was installed on the upper wiring 102 in the same manner as in Example 1.

  The face plate 612 used was the same as that of the first embodiment except that a φ8 exhaust port 613 was opened inside the outer frame 105 outside the image area. Further, as in the first embodiment, the phosphor film 111, the black conductive material, and the metal back film 110 are manufactured, and the same ion pump container 115 as that in the first embodiment is formed in the exhaust port of the face plate 612 in the same manner as in the first embodiment. Bonded onto 613. Further, In107 was applied on a silver paste pattern provided in advance on the peripheral edge of the face plate 612, and In was also applied on the support frame 105.

  Next, the rear plate 601 to which the support frame 105 was joined and the face plate 612 to which the ion pump container 115 was joined were joined using the vacuum processing apparatus shown in FIG. In the sealed container thus produced, no cracks or cracks occurred.

  Next, the magnet 121 was fixed and the yoke 122 was fixed as in Example 1. At this time, the component parallel to the rear plate 101 of the magnetic flux density at the location of the surface conduction electron-emitting device 104 closest to the magnet 121 was 0.008T.

  Next, a DC voltage of 10 kV is applied to the metal back film 110 from a high-voltage power supply (not shown), and a voltage of 3 kV is applied so that the anode electrode 119 becomes positive at the anode connection terminal 120 and the cathode connection terminal 118 of the ion pump 123. Was applied. Further, a scanning signal and a modulation signal as image signals are applied to the surface conduction electron-emitting device 104 from a scanning driving circuit (not shown) connected to the upper wiring 102 and a modulation driving circuit (not shown) connected to the lower wiring 103. The image was displayed. Even in the image region closest to the ion pump 123, 49 out of 50 judges judged that there was no problem in image non-uniformity and color shift.

<Example 3>
In this embodiment, an example using a field emission type electron-emitting device 700 as an electron source as shown in FIG. 7 will be described. As shown in the figure, a negative electrode 702, a positive electrode 703, and an electron emission portion 705 that emits electrons having a sharp tip are formed in an insulating layer 704 on a rear plate 701, and a field emission electron emission device is formed. 700 is configured. In such a configuration, when a voltage is applied to the positive electrode 703 and the negative electrode 702 so that the positive electrode 703 has a high potential, an electric field is concentrated on the electron emission portion 705 and electrons are emitted from the electron emission portion 705 by a tunnel effect.

A method for creating the image display apparatus of this embodiment will be described below. The rear plate 701 uses the same substrate as that of the first embodiment. First, the field emission type electron-emitting device 700 is formed on the rear plate 101. The negative electrode 702 and the positive electrode 703 are made of Mo having a thickness of 0.3 μm, the field emission portion 705 has a tip angle of 45 degrees, the electron source corresponding to one pixel has 100 electron emission portions 705, and is insulated. As the layer 704, SiO ₂ having a thickness of 1 μm was used. Mo and SiO ₂ were deposited by a sputtering method, and the processing was performed by a photolithography technique (including processing techniques such as etching and lift-off). Next, the upper wiring 102 and the lower wiring 103 having the same structure and members were formed by the same method as in the first embodiment. It should be noted that a part of the positive electrode 703 is in electrical contact with the lower wiring 103 and a part of the negative electrode 702 is in electrical contact with the upper wiring 102. Further, a rear plate 701 and a face plate (not shown) in which the same ion pump container 115 is joined using the same structure and members by the same method as in Example 1 were prepared. The rear plate 701 and the face plate were joined using the vacuum processing apparatus shown in FIG. In the sealed container thus produced, no cracks or cracks occurred.

  Next, the magnet 121 was fixed and the yoke 122 was fixed as in Example 1. At this time, the component of the magnetic flux density parallel to the rear plate 101 at the location of the field emission electron-emitting device 700 closest to the magnet 121 was 0.009T.

  Next, a DC voltage of 10 kV is applied to the metal back film 110 from a high-voltage power supply (not shown), and a voltage of 3 kV is applied so that the anode electrode 119 becomes positive at the anode connection terminal 120 and the cathode connection terminal 118 of the ion pump 123. Is applied to the field emission type electron-emitting device 700 from a scanning drive circuit (not shown) connected to the upper wiring 102 and a modulation driving circuit (not shown) connected to the lower wiring 103. A signal was applied to display an image. Even in the image region closest to the ion pump 123, 49 out of 50 judges judged that there was no problem in image non-uniformity and color shift.

<Example 4>
In this embodiment, an example in which a speaker that converts an audio signal into sound is installed as shown in FIG. 8 will be described. In the figure, a speaker 800 includes a vibrating portion 801, a magnet 802, and a yoke 803, and is attached to a case 804 of the image display device. Although the ion pump 123 is installed, it is not shown in FIG. 8, and other members having the same reference numerals as those shown in the drawings so far indicate the same members.
First, an image display device was manufactured in the same manner as in Example 1 except for the speaker 800. Next, the speaker 800 was installed. At this time, the component of the magnetic flux density parallel to the rear plate 101 at the location of the surface conduction electron-emitting device 104 closest to the magnet 802 was 0.008T. Next, the case 804 was attached.

  Next, a DC voltage of 10 kV is applied to the metal back film 110 from a high voltage power source (not shown), and a voltage of 3 kV is applied so that the anode electrode 119 becomes positive at the anode connection terminal 120 and the cathode connection terminal 118 of the ion pump 123. The scanning drive circuit (not shown) connected to the upper wiring 102 and the modulation driving circuit (not shown) connected to the lower wiring 103 to the surface conduction electron-emitting device 104 and the scanning signal as an image signal and modulation. A signal was applied to display an image. In the image area closest to the speaker 800, 48 out of 50 judges judged that there was no problem with image non-uniformity and color shift.

  As described above, in the image display device of the present invention, the influence on the electron trajectory is reduced by setting the component parallel to the inner rear plate of the magnetic flux density at the position of the electron generating means to be 0.01 Tesla or less. It is now possible to provide an image display device that does not recognize luminance variations and color irregularities. In addition, since the ion pump and the speaker having the magnet can be brought close to the limit, a compact image display device can be provided.

It is a schematic block diagram which shows 1 aspect of the image display apparatus by this invention. It is a figure explaining an electron source. It is a figure explaining the apparatus which performs a forming and activation process. It is a schematic block diagram of a vacuum processing apparatus. It is a figure explaining the baking in a vacuum processing apparatus, a getter flash, and a sealing process. It is a schematic block diagram which shows 1 aspect of the image display apparatus by this invention. It is a schematic block diagram of a field emission type electron-emitting device. It is a schematic block diagram which shows the Example which installed the speaker. It is a figure explaining a prior art.

Explanation of symbols

101, 601, 701 Rear plate 104 Surface conduction electron-emitting device 105 Support frame 107 Joining member 108 Spacer 109 Getter film 110 Metal back film 111 Phosphor film 112, 612 Face plate 115 Ion pump vessel 116 Cathode electrode 119 Anode electrode,
121 Magnet 123 Ion pump 202, 203 Element electrode 204 Electron emission unit 205 Conductive thin film 301 Vacuum vessel 303 Substrate stage 305 Magnetic levitation turbomolecular pump 402 Load chamber 403 Vacuum processing chamber 404 Transport jig 503 Cover jig 504 Upper hot Plate 505 Lower hot plate 700 Field emission type electron-emitting device 705 Electron emission unit 800 Speaker 802 Magnet 902 Front panel 910 Vacuum vessel 905 Electrode structure 908 Ion pump 912 Anode 913 Cathode 920 Magnetic field generating means

Claims (6)

An image display device comprising: an electron source substrate on which a plurality of electron-emitting devices are arranged; an image forming substrate disposed opposite to the electron source substrate and having a fluorescent film and an anode electrode film; and a magnetic field generating means. ,
An image display device, wherein a component parallel to the electron source substrate of the magnetic flux density of the magnetic field generated by the magnetic field generating means is 0.01 Tesla or less at the position of the electron-emitting device.   2. The image display device according to claim 1, wherein the magnetic field generating means is a permanent magnet of an ion pump connected to the electron source substrate or the image forming substrate.   The image display device according to claim 2, wherein the magnetic field generating means is a single permanent magnet having a pair of magnetic poles.   4. The image display device according to claim 3, wherein the direction of the magnetic pole is substantially perpendicular to the electron source substrate.   2. The image display device according to claim 1, wherein a distance between the magnetic field generating means and the electron emitting element that is closest to the magnetic field generating means is 5 mm or more.   The image display apparatus according to claim 1, wherein the magnetic field generating means is a permanent magnet attached to a speaker.

Images